In this process in a refrigerant line arranged downstream of the refrigerant evaporator a heatable measuring unit is inserted. The refrigerant flows around it. The measuring unit is heated to a temperature which is greater than that of the refrigerant. The impact of liquid drops of the refrigerant on the measuring unit and therewith the moisture content of the gas originating from the refrigerant evaporator is established by measuring the energy required to evaporate the liquid drops impacting the measuring unit.
Such processes are known from DE-OS 39 34 801 and DE-OS 40 06 040. During the implementation of the known process in connection with the refrigerators described in both cited references it has been found that an optimal setting, control and monitoring of the level in the refrigerant evaporator based on the measuring signals at the measuring unit cannot always be achieved during the operation of the refrigerator. This is due in part, to insufficient signal processing.